Method of reducing power consumption in a network

Abstract

A method of reducing power consumption in a network. A first network device powers down or reduces the port speed of a port if said port is blocked by a loop mitigation protocol.

What is claimed is: 
     
       1. A method of reducing power consumption of a first network device in a network, wherein the first network device includes a first port communicatively connected to a second network device via a link, the method comprising:
 determining, by the first network device, that the first port of the first network device is blocked by a loop mitigation protocol; 
 in response to determining that the first port is blocked, sending a message from the first network device to the second network device to inform the second network device that a speed of the link will be reduced from an original speed to a reduced speed; 
 receiving an acknowledgement from the second network device; 
 in response to receiving the acknowledgement from the second network device, reducing by the first network device a speed of the first port to reduce the speed of the link from the original speed to the reduced speed; and 
 advertising, by the first network device, the link as having the original speed in a message sent to a third network device. 
 
     
     
       2. The method of  claim 1 , wherein the message sent from the first network device to the second network device to inform the second network device that the speed of the link will be reduced is further to request the second network device to advertise the link as having the original speed. 
     
     
       3. The method of  claim 1 , wherein reducing the speed of the first port comprises reducing the speed of the first port to zero to disable the link between said first port of said first network device and a port of the second network device. 
     
     
       4. The method of  claim 1 , further comprising:
 negotiating, by the first network device, with the second network device, which of the first and second network devices will power down a port connected to the link. 
 
     
     
       5. The method of  claim 4 , wherein the powered down port is periodically powered up. 
     
     
       6. The method of  claim 1 , further comprising:
 sending, by the first network device, loop mitigation protocol messages to the second network device by encapsulating the loop mitigation protocol messages and sending them indirectly to the second network device via a path which does not include the blocked port. 
 
     
     
       7. The method of  claim 1 , further comprising:
 switching, by the first network device, the first port back to the original speed in response to the first network device detecting a change in network topology or a change in a status of the first port under the loop mitigation protocol. 
 
     
     
       8. The method of  claim 1 , wherein the first network device operates in one of a plurality of loop mitigation protocol regions, and wherein the method further comprises reducing, by the first network device, the speed of the first port blocked by the loop mitigation protocol in response to the first port being linked to a network device in another loop mitigation protocol region of the network and in response to the first port having no direct links to other network devices in the another loop mitigation protocol region of the network. 
     
     
       9. A first network device comprising:
 a first port communicatively connected to a second network device via a link; 
 a processor; and 
 a memory, the memory storing machine readable instructions which are executable by the processor to:
 determine that the first port has been blocked by a loop mitigation protocol, 
 in response to the determination that the first port has been blocked by the loop mitigation protocol, send a message to the second network device to inform the second network device that a speed of the link will be reduced from an original speed to a reduced speed and request the second network device to advertise to other network devices that the link has the original speed, 
 receive an acknowledgement from the second network device, and 
 in response to receipt of the acknowledgement from the second network device, reduce a speed of the first port to reduce the speed of the link from the original speed to the reduced speed. 
 
 
     
     
       10. The first network device of  claim 9 , wherein the machine readable instructions comprise instructions to negotiate a reduced link speed for the link between the first port of the first network device and a port of the second network device, the reduced link speed being lower than the original speed; and to send a message to a third network device indicating that the speed of the link between said first and second network devices is the original speed. 
     
     
       11. The first network device of  claim 9 , wherein the machine readable instructions comprise instructions to operate the first port at the original speed in response to a detected change in network topology or a detected change in a status of the first port under the loop mitigation protocol. 
     
     
       12. The first network device of  claim 9 , wherein the machine readable instructions comprise instructions to implement a multi-instance loop mitigation protocol, wherein said instructions to reduce the speed of the first port are implemented only if the first port has a link to a network device in another region of the network and if the first port has no direct links to other network devices in the another region of the network. 
     
     
       13. A first network device comprising:
 a first port communicatively connected to a second network device via a link; 
 a processor; and 
 a memory, the memory storing machine readable instructions which are executable by the processor to:
 determine that the link is blocked by a loop mitigation protocol, 
 in response to the determination that the link is blocked by the loop mitigation protocol, send a message to the second network device to inform the second network device that the link will be disabled, 
 receive an acknowledgement from the second network device, and 
 in response to receipt of the acknowledgement from the second network device, disable the link between the first network device and the second network device, wherein the first port is switched off, 
 
 wherein the machine readable instructions comprise instructions to implement a multi-instance loop mitigation protocol, wherein the machine readable instructions to switch off the first port are implemented only if the first port has a link to a network device in another region of the network and if the first port has no direct links to other network devices in a same region of the network as the first network device. 
 
     
     
       14. The first network device of  claim 13 , wherein the machine readable instructions comprise instructions to negotiate with the second network device which of the first and second network devices will power down a port connected to the link. 
     
     
       15. The first network device of  claim 13 , wherein the machine readable instructions comprise instructions to periodically power up the link in order to send a control message before switching the first port off again. 
     
     
       16. The first network device of  claim 13 , wherein the machine readable instructions comprise instructions to send loop mitigation protocol messages to the second network device by encapsulating the loop mitigation protocol messages and sending them indirectly to the second network device via a path which does not include the first port. 
     
     
       17. The first network device of  claim 13 , wherein the machine readable instructions comprise instructions to switch on said first port in response to detecting a change in network topology.